Getting abstractions wrong with AWS SAM Serverless Connectors

I was intrigued when I first saw the announcement of AWS SAM Serverless Connectors. I don’t use SAM very much (if at all anymore), so it wasn’t the hope of this being some sort of silver bullet for my occasional IAM frustrations that got my attention. Rather, it was another opportunity to learn how AWS is trying to abstract away their mostly self-imposed complexity problems. Unfortunately, I think they missed the mark on this.

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Jeremy’s Guide to a Very Serverless re:Invent 2020

It’s AWS re:Invent time, and once again, developers, architects, business leaders, and everyone in between are faced with the daunting task of selecting from thousands of hours of re:Invent content. As usual, I will be focusing most of my time on serverless, so I’ve combed through the massive session catalog and picked out the ones that look the most interesting to me. If you’re looking to focus on serverless during this re:Invent, perhaps you’ll find my suggestions useful.

My picks are also available on the Cloud Pegboard re:Invent Tool (Thanks, Ken). Select “Jeremy Daly” from the “AWS Hero Picks” dropdown and you’ll see all my selections with the options to add them to your wishlist and export them to your calendar. I have about 60 sessions on my list, which I’ve categorized below. But I realize that no human is likely going to be able to watch them all, so I’ve also made a list of Sessions you can’t miss!

There are sure to be plenty of announcements throughout the three weeks of re:Invent, so be sure to subscribe to the Off-by-none newsletter for weekly recaps.

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Verifying self-signed JSON Web Tokens (JWTs) with AWS HTTP APIs

“Trust no one.” Or at least that’s what Fox Mulder told me back in the 90s.

With the recent GA of HTTP APIs for API Gateway, I decided to start evaluating my existing API Gateway REST APIs to see if I could migrate them over to take advantage of the decreased latency and reduced cost of the new HTTP APIs. Several of them were disqualified because they utilize service integrations (a feature that AWS is working to add), but for one of my largest applications, the lack of Custom Authorizers is what brought me to a dead end. Or so I initially thought. 😉

After a bit of research (okay, it was actually several hours because I decided to read through a bunch of specs and blog posts and then run a ton of experiments), it turns out that hosting your own OIDC Conformant “server” to verify self-signed JSON Web Tokens with HTTP APIs is actually quite simple. So as long as you can use JWT for your bearer tokens, you can utilize your existing authentication service (and probably dramatically reduce your latency and cost).

In this post, I’ll show you everything you need to know to set this up yourself. We’ll generate certificates, create our OIDC discovery service, set up our HTTP API authorizers, generate and sign our JWTs, and protect routes with scopes.

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Serverless Security: Locking Down Your Apps with FunctionShield

I’ve written quite extensively about serverless security, and while you don’t need to be an expert on the matter, there are a number of common sense principles that every developer should know. Serverless infrastructures (specifically FaaS and managed services) certainly benefit from an increased security posture given that the cloud provider is handling things like software patching, network security, and to some extent, even DDoS mitigation. But at the end of the day, your application is only as secure as its weakest link, and with serverless, that pretty much always comes down to application layer security.

In this post we’re going to look at ways to mitigate some of these application layer security issues by using some simple strategies as well as a free tool called FunctionShield.

Audio Version:

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5 Reasons Why Your Serverless Application Might Be A Security Risk

There has been a lot of buzz lately about serverless security. People are certainly talking about it more and sharing great articles on the topic, but many serverless developers (especially new ones) are still making the same critical mistakes. Every time a serverless function is deployed, its unique security challenges need to be addressed. Every time. I’ve researched and written extensively about serverless security (see Securing Serverless: A Newbie’s Guide). I’ve read countless articles on the subject. And while there is no shortage of information available, let’s be honest: developers are busy building applications, not pouring through hundreds of articles.

I know, it sounds boring, but I would encourage you to do your research on serverless security. Serverless applications are different than traditional, server-hosted applications. Much of the security responsibility falls on the developer, and not following best practices opens you (or your company) up to an attack. But I know you’re busy. I totally get it. So rather than forcing you to read a bunch of long articles 😴 or watch a plethora of videos 🙈, I’ve whittled it all down to the five biggest serverless security risks for you. Sure, there are a lot of other things to consider, but IMO, these are the most important ones. Nothing here hasn’t been said before. But If you do nothing more than follow these principles, your serverless applications will be much more secure. 🔒

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Event Injection: Protecting your Serverless Applications

Updated January 25, 2019: This post was updated based on feedback from the community.

The shared security model of cloud providers extends much further with serverless offerings, but application security is still the developer’s responsibility. Many traditional web applications are front-ended with WAFs (web application firewalls), RASPs (runtime application self-protection), EPPs (endpoint protection platforms) and WSGs (web security gateways) that inspect incoming and outgoing traffic. These extra layers of protection can save developers from themselves when making common programming mistakes that would otherwise leave their applications vulnerable. If you’re invoking serverless functions from sources other than API Gateway, you no longer have the ability to use the protection of a WAF. 

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10 Things You Need To Know When Building Serverless Applications

I am a HUGE fan of serverless architectures. This new type of compute not only opens up more possibilities for developers, but can support highly-scalable, complex applications for a fraction of the cost compared to provisioning virtual servers. My first question when planning a new application is always, “Can I build this with serverless?” Spoiler alert, the answer is almost always YES!

I’ve been building serverless applications since the release of AWS Lambda in 2015, so answering the question above is pretty easy for me. However, a lot of people I talk to who are new to serverless often have many questions (and misconceptions). I want you to be successful, so below I’ve create a list of 10 things you need to know when building a serverless application. These are things I wish I knew when I started, so hopefully they’ll help you get up to speed a faster and start building some amazing applications.

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Securing Serverless: A Newbie’s Guide

So you’ve decided to build a serverless application. That’s awesome! May I be the first to welcome you to the future. 🤖 I bet you’ve done a lot of research. You’ve probably even deployed a few test functions to AWS Lambda or Google Cloud Functions and you’re ready to actually build something useful. You probably still have a bunch of unanswered questions, and that’s cool. We can still build some really great applications even if we only know the basics. However, when we start working with new things we typically make a bunch of dumb mistakes. While some are relatively innocuous, security mistakes can cause some serious damage.

I’ve been working with serverless applications since AWS launched Lambda in early 2015. Over the last few years I’ve developed many serverless applications covering a wide range of use cases. The most important thing I’ve learned: SECURE YOUR FUNCTIONS! I can tell you from personal experience, getting burned by an attack is no bueno. I’d hate to see it happen to you. 😢

To make sure it doesn’t happen to you, I’ve put together a list of 🔒Serverless Security Best Practices. This is not a comprehensive list, but it covers the things you ABSOLUTELY must do. I also give you some more things to think about as you continue on your serverless journey. 🚀

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How To: Access Your AWS VPC-based Elasticsearch Cluster Locally

AWS recently announced that their Elasticsearch Service now supports VPC, which is awesome, for a number of reasons:

1. No more signing every request

Remember this?

Every request had to be signed with AWS’s SigV4 so that the Elasticsearch endpoint could be properly authorized. That meant additional code to sign all your requests, and additional time for the endpoint to decode it. It might only be a few milliseconds of extra processing time, but those can add up. Now we can call our VPC Elasticsearch endpoint with a simple HTTP request.

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